Preliminary autopsy findings of second
baboon liver recipient released

PITTSBURGH, Feb. 17, 1993 -- The preliminary results of an autopsy performed on
the second baboon-to-human liver transplant recipient, who died Feb. 5, revealed that the
probable cause of death was the complications arising from overwhelming infection.

The transplant, which was performed on Jan. 10 at the University of Pittsburgh Medical
Center (UPMC), was followed by an early episode of rejection. The rejection was controlled
with medication. The liver subsequently grew more than three times its original size
within three weeks after transplantation. During this period of growth, there was no
evidence of any further rejection. However, an infection was found four days prior to the
patient's death. The infection was thought to be caused by a leak from the small
intestine. The cause of the leak has not been determined.

"Prior to the discovery of the infection, the liver consistency was normal and
functioned, as evidenced by the production of bile and normal coagulation parameters. Even
at autopsy there did not appear to be any immunological damage to the liver blood vessels,
although there was terminal damage to the liver from the infection", said John Fung,
M.D., Ph.D., chief of transplantation at the UPMC.

Results of additional studies of tissues to look for evidence of chimerism, the
coexistence of both baboon and human cells; and of the effects, if any, of the bone marrow
infusion, are not yet known. These and other clinical findings, including those related to
metabolism and liver functions, will be released by the transplant team when an article is
published in a medical journal.

Last summer, the university's Institutional Review Board (IRB) gave
approval for four baboon-to-human liver transplants to be performed in patients with
chronic, active hepatitis B, for whom there is no other medical option. IRB approval is
contingent on a case-by-case review. The transplant team will not proceed with further
human trials until an analysis of current clinical information is complete.